Not Applicable
Not Applicable
Not Applicable
This invention relates to the field of packaging machinery, particularly machines for erecting or squaring cases and folding the bottom flaps in preparation for filling and closing. The cases are typically shipping cases into which single or multiple articles are placed for storage and transport to retailers or end users. These machines typically contain a quantity of identical cases, held in a magazine, which are removed, squared, and transported, one at a time, out of the machine.
Known machinery of this type currently in use typically utilizes suction cups to grip the case, then extract it from the magazine and manipulate it into a squared configuration using various combinations of reciprocating linear and/or rotary motions. The bottom minor flaps are then closed by flap folding mechanisms. The bottom major flaps may also be closed by similar mechanisms, or by stationary ploughs which force the major flaps closed as the case is conveyed out of the squaring area. One common conveying means is a reciprocating carrier, traveling along a linear path. This carrier may contain the extracting and squaring means, and may drive the case from behind or by the gripped sides of the case. Another common conveying means consists of a pair of rotating side drive belts which the case is inserted between after it is squared.
There are generally two basic configurations for this type of machinery, determined by the path taken by the cases as they move through the machine. The first is an xe2x80x9cLxe2x80x9d-shaped configuration, wherein the case is extracted from the magazine and conveyed along a path at a ninety degree angle to the flow of cases from the magazine. The second is an xe2x80x9cin-linexe2x80x9d configuration, wherein the case is extracted from the magazine and conveyed along a path common to or along the same line as the flow of cases from the magazine. With this type of configuration, the cases xe2x80x9cflow throughxe2x80x9d the machine.
These machines are adjustable to handle a variety of case sizes, within a specified range. There are usually several adjustments that must be made during a changeover from one case size to another. These adjustments include magazine height (to compensate for varying bottom flap length), left and right magazine side guide position, magazine case top support position, squaring mechanism position, bottom flap kicker positions, and conveying means side guide positions. These adjustments are typically made individually, using scales mounted on the mechanisms and measured dimensions of the case, or the case itself as a gauge. Thus, a typical case size changeover may involve as many as nine individual adjustments.
Examples of the previously described machines include the following U.S. Pat. Nos. Re. 27631; 4,439,174; 3,739,696; 4,627,830; 4,632,666; 4,285,679 and 5,156,582.
As can be seen in the prior art, many of the mechanisms used in current machines are complex and elaborate, making them more expensive to manufacture and difficult to adjust and maintain. These machines use some form of reciprocating linear motion in the squaring and/or conveying operations. As opposed to reciprocating rotary mechanisms, reciprocating linear mechanisms are typically more expensive to construct due to the cost of linear bearings and substantial structure required in order to achieve stability and reliability. Due to increased mass, reciprocating linear mechanisms typically require more area within the machine, more energy to operate, and are more limited in terms of operating speed than reciprocating rotary mechanisms.
Many of the prior art machines are of the xe2x80x9cLxe2x80x9d configuration, which typically occupies more floor space than the xe2x80x9cin-linexe2x80x9d configuration machine, and utilizes this floor space less efficiently. The xe2x80x9cLxe2x80x9d configuration also deems necessary the offering of left-hand and right-hand models to accommodate customers differing layout requirements.
As detailed earlier, most prior art machines have numerous adjustments which must be made individually, which leads to time-consuming and complicated changeovers. Additionally, the accuracy of these adjustments is difficult to achieve and replicate, which can mean xe2x80x9cdebuggingxe2x80x9d the machine after each changeover.
The primary object of the invention is to provide a case erector that is mechanically simple, with the minimum number of moving parts.
Another object of the invention is to provide a case erector where simple rotary motions perform all the necessary functions.
Another object of the invention is to provide a case erector that is relatively inexpensive to manufacture.
A further object of the invention is to provide a case erector having the preferable xe2x80x9cin-linexe2x80x9d magazine configuration and a relatively small footprint.
Yet another object of the invention is to provide a case erector that allows for simple mechanical coupling of several changeover adjustments, meaning simpler changeovers with less steps and better accuracy.
Other objects and advantages of the present invention will become apparent from the following descriptions, taken in connection with the accompanying drawings, wherein, by way of illustration and example, an embodiment of the present invention is disclosed.
In accordance with a preferred embodiment of the invention, there is disclosed a mechanism for squaring flattened case blanks, folding the bottom flaps and delivering them in preparation for use. A magazine section contains a plurality of flattened case blanks, each case blank having a first major side panel, a first outer folded corner adjacent to the first major side panel, a second outer folded corner on the opposite end of the case blank from the first outer folded corner, two bottom major flaps, and two bottom minor flaps. A pivotally mounted arm with suction cups attached grips the lead case blank by the first major side panel, leaving the remaining three side panels free to rotate about its four corners. A curved structure is mounted in the path of the rotating case blank in a position where it will making contact with the second outer folded corner. The curved structure is formed in such a manner that it causes the distance between the outer folded corners to gradually decrease as the case blank rotates. The case blank is forced into a squared configuration as it reaches 90 degrees of rotation.
The bottom minor flaps are then folded by flap kickers as the major side panels of the case are gripped between two drive belts, one stationary, and one with a gate-like swinging section. The drive belts convey the case over major flap ploughs, which close the bottom major flaps, and out of the machine.